Jacek wrote:
> do you need any particular polarisation to couple
> to the magnetosphere?
The whistlers emerge more or less circular polarised. But
unless you are under the duct exit they will be less circular
and more linear.
A recent whistler in the two opposite circular polarisations.
http://abelian.org/vlf/tmp/170218a.png
The top trace responds to signals rotating anti-clockwise as
you look up towards the incoming signal. The lower trace
responds to clockwise
I had to go back a couple of days to find one that was fairly
strongly polarised for this example. Most whistlers arriving
here are coming from further east and are more linear.
> now i do :)
> and there is indeed a lot of whistlers
I would be interested to compare the number of events you
log with the whistler counts from Bielefeld.
Eg in the event directory: ls 148745*.vt | wc -l (after 23:20 UT!)
to compare with the same count from Bielefeld.
Bielefeld on average has 2.7 whistlers for each whistler in the
UK. I've often wondered if there are even more frequent
whistlers further east. It's all a matter of where the
lightning storms tend to happen.
The storm is moving east, whistler count at Bielefeld
is reducing. I expect the count will increase further east.
The best 30 minutes of this afternoon's whistlers recorded
on Wolf's receiver:
http://78.46.38.217/vlf6.170218b.mp3 (24 Mbytes)
--
Paul Nicholson
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